[High expression of fragile X mental retardation protein inhibits ferroptosis of colorectal tumor cells by activating the RAS/MAPK signaling pathway].

OBJECTIVE: To investigate the mechanism by which fragile X mental retardation protein (FMRP) regulates ferroptosis evasion in colorectal cancer (CRC) cells. METHODS: We examined FMRP expression levels in CRC cell lines using RT-qPCR and Western blotting and analyzed the biological functions and signaling pathways involved in FMRP-mediated regulation of CRC progression using the TCGA database. A lentiviral FMRP overexpression vector (Lv-FMRP) and 3 knockdown vectors (siFMRP-1, siFMRP-2, and siFMRP-3) were constructed, and their effects on proliferation of HCT116 cells were examined using CCK8 assay and plate clone formation assay; the changes in cell ferroptosis level was determined using MDA/ROS/GSH/Fe2+ kits, mitochondrial membrane potential changes were detected using JC-1 fluorescence staining, and the expressions of proteins associated with ferroptosis and the RAS/MAPK signaling pathway were detected using Western blotting. The subcutaneous tumorigenic potential of the transfected cells was evaluated in nude mice. RESULTS: Compared with normal colonic mucosal epithelial NCM460 cells, the CRC cell lines had significantly higher FMRP expression level. Bioinformatics analysis suggested the involvement of FMRP in regulation of reactive oxygen, oxidative stress-induced cell death, mitochondrial respiration, and glutathione metabolism pathways. In the cell experiments, FMRP knockdown significantly inhibited proliferation of HCT116 cells, lowered cellular GSH content, increased MDA and ROS levels, Fe2+ fluorescence intensity, and mitochondrial membrane potential, and decreased SLC7A11/GPX4 protein expressions and the phosphorylation levels of ERK, MEK, MAPK, and RAS proteins; FMRP overexpression resulted in the opposite changes in the cells. In the tumor-bearing nude mice, HCT116 cells with FMRP knockdown showed attenuated tumorigenic potential with lowered xenograft growth rate and reduced SLC7A11 expression in the xenograft. CONCLUSION: The high expression of FMRP inhibits ferroptosis in CRC cells and promotes progression of CRC by activating the RAS/MAPK signaling pathway.

Abrupt change reflected by the van Hove singularity in the optical spectra of CaMn2P2.

The trigonal CaAl2Si2-type structure CaMn2P2has been reported undergoing an exotic first order phase transition at the critical temperatureTN=69.5K. In this paper, we present the optical spectra for theab-plane of CaMn2P2single crystal from 300 K to 10 K for the first time. In the real part of the optical conductivity spectraσ1(ω), a direct gap could be determined at all temperatures without any Drude term visible, i.e., the sample goes through the first order phase transition from one insulator state to the other insulator state. At higher energy, an asymmetric sharp interband transition peak appears in allσ1(ω) spectra, which indicates a divergence of the joint density of states. This sharp peak could be well described by the two dimensional van Hove singularity function. In particular, this peak is very sensitive to the first order phase transition, especially the peak positionEtwhose the most prominent blue shift occurs only when the first order transition happens. Our data and analysis reveal that the first order phase transition leads to a weak partial re-normalization of the band structure. Our study will be useful in further investigations about the mechanism of the first order phase transition in the insulator.

Gout-like hands.

A 65-year-old man presented to our hospital with a 1-year history of multiple nodules on his arms and hands without itching or pain.

Emergency management of 2019 novel coronavirus: implications for the dermatology department.

Since cases first emerged in December 2019, COVID-19 (a type of coronavirus) has rapidly become pandemic. This fast-tracked paper (published quickly) from China on COVID-19 is written by dermatologists at the epicentre of the outbreak in Wuhan. Dermatology clinic staff may be at risk because protective equipment is not routinely available, and skin lesions might possibly transmit the virus indirectly. These authors suggest preventive measures based on experience in this and previous coronavirus outbreaks. Online consultation for non-urgent patients reduces the numbers of patients attending clinics. Nurse-led triage, to identify patients with possible COVID-19, at the entrances of hospital and skin clinics directs patients with a cough or fever to a specific COVID-19 area and a dermatologist is consulted if the fever might be related to skin disease. Clinic staff wear N95 masks and observe hand hygiene during consultations. Patients are admitted to a ward only if routine blood tests and chest CT scans exclude COVID-19. Triage will not detect patients who are showing no symptoms but who are developing the disease, so the hospital should provide an on-call expert team to discuss inpatients suspected or diagnosed with COVID-19 and refer them to radiology, respiratory or intensive care colleagues as required. Confirmed cases are managed following local policies. Skin disorders in COVID-19 inpatients can usually be managed remotely using photographs, email and teleconferencing. If necessary a multidisciplinary team (a team of medical staff from different specialties) can meet in the clean area of the isolation ward. If the dermatologist must see the patient, all records should be provided in advance to minimise exposure time. With these precautions, as of 20th February 2020 no infected patients were detected in the Wuhan Dermatology Department. This is a summary of the study: Emergency management for preventing and controlling nosocomial infection of 2019 novel coronavirus: implications for the dermatology department.

Effects of pheophorbide a-mediated photodynamic therapy on proliferation and metastasis of human prostate cancer cells.

OBJECTIVE: To observe the effects of pheophorbide a-mediated photodynamic therapy (Pa-PDT) on the in vitro proliferation, apoptosis, invasion and metastasis of human prostate cancer PC-3 cells and to investigate its possible mechanism. MATERIALS AND METHODS: Pa-PDT in gradient concentrations (0 µM, 0.25 µM, 0.5 µM, 1 µM, 2 µM, and 4 µM) were used to act on PC-3 cells; the cell proliferation in each group was detected via methyl thiazolyl tetrazolium (MTT) assay and clone formation assay, and the cell apoptosis was detected via Hochst33258 staining and Annexin V/propidium iodide (PI) double labeling. Moreover, the effects of Pa-PDT on invasion and proliferation of PC-3 cells were observed via wound healing assay and transwell chamber assay. Finally, the expressions of apoptosis-related proteins, epithelial-mesenchymal transition (EMT)-related proteins and matrix metalloproteinases (MMPs) in each group were detected after treatment by Western blotting. RESULTS: MTT and clone formation assays showed that Pa-PDT could inhibit the proliferation of PC-3 cells in a dose-dependent manner. The results of apoptosis assay revealed that Pa-PDT could significantly promote the apoptosis of PC-3 cells, obviously up-regulate the expressions of pro-apoptotic proteins, such as B-cell lymphoma-2-associated X protein (BAX), Caspase-3 and poly adenosine diphosphate-ribose polymerase (PARP), and inhibit the expression of Bcl-2. Besides, the wound healing assay and Transwell chamber assay showed that Pa-PDT could inhibit the invasion and metastasis capacities of PC-3 cells, whose relevant mechanisms were related to the fact that Pa-PDT inhibited the EMT process and down-regulated the expressions of MMPs in PC-3 cells. CONCLUSIONS: Pa-PDT can inhibit the proliferation and promote the apoptosis of PC-3 cells. Moreover, it can also inhibit the invasion and metastasis capacities of PC-3 cells via inhibiting the EMT process and down-regulating the expressions of MMPs.

Role of endothelin-1 in the skin fibrosis of systemic sclerosis.

Endothelin-1 (ET-1) acts as a key regulator of vasoconstriction and fibrosis. Many previous studies have focused on the role of ET-1 in scleroderma (systemic sclerosis, SSc). We investigated the effects of ET-1 on the production of extracellular matrix in SSc and normal skin fibroblasts. Primary cultured dermal fibroblasts from SSc patients and healthy controls were treated with ET-1 (25 ng/mL) for 0 min, 15 min, 1 h, 24 h, 48 h and 72 h, respectively. Our results showed that, in SSc fibroblasts, ET-1 upregulated collagen type I, connective tissue growth factor (CTGF), type I plasminogen activator inhibitor (PAI-1) and pAkt in a time-dependent manner within 72 h; in normal fibroblasts, 25 ng/mL ET-1 stimulation correlated with high levels of CTGF, PAI-1 and pAkt. The secretion of fibronectin (FN), collagen type I, and PAI-1 is markedly increased in the supernatant of both SSc fibroblasts and normal fibroblasts. Furthermore, ET-1 phosphorylates Smad2 and Smad3 in normal fibroblasts, but not in SSc fibroblasts. In conclusion, our results demonstrated that ET-1 may induce fibrosis in dermal fibroblasts through Akt signals.

Androgen receptor signaling regulates DNA repair in prostate cancers.

UNLABELLED: We demonstrate that the androgen receptor (AR) regulates a transcriptional program of DNA repair genes that promotes prostate cancer radioresistance, providing a potential mechanism by which androgen deprivation therapy synergizes with ionizing radiation. Using a model of castration-resistant prostate cancer, we show that second-generation antiandrogen therapy results in downregulation of DNA repair genes. Next, we demonstrate that primary prostate cancers display a significant spectrum of AR transcriptional output, which correlates with expression of a set of DNA repair genes. Using RNA-seq and ChIP-seq, we define which of these DNA repair genes are both induced by androgen and represent direct AR targets. We establish that prostate cancer cells treated with ionizing radiation plus androgen demonstrate enhanced DNA repair and decreased DNA damage and furthermore that antiandrogen treatment causes increased DNA damage and decreased clonogenic survival. Finally, we demonstrate that antiandrogen treatment results in decreased classical nonhomologous end-joining. SIGNIFICANCE: We demonstrate that the AR regulates a network of DNA repair genes, providing a potential mechanism by which androgen deprivation synergizes with radiotherapy for prostate cancer.

Expression of pigment epithelium-derived factor in human cutaneous appendages.

BACKGROUND: Pigment epithelium-derived factor (PEDF), a 50-kDa glycoprotein and a member of the serine protease inhibitor gene family, is well known as a potent endogenous inhibitor of angiogenesis. However, the expression of PEDF in human cutaneous appendages has not yet been determined. AIM: To investigate the expression of PEDF in human cutaneous appendages. METHODS: Immunohistochemical staining was used to detect the expression of PEDF in human cutaneous appendages. Reverse transcriptase PCR, western blotting and indirect immunofluorescence were used to determine the mRNA and protein expression of PEDF on cells of the outer root sheath (ORS). A wound-healing assay was used to determine the effect of different concentrations of PEDF on the migration of ORS cells. RESULTS: PEDF was expressed in the hair follicle (including epidermal matrix, inner root sheath, ORS and fibrous root sheath), sebaceous glands and eccrine sweat glands. Both protein and RNA expression of PEDF was detected, and expression was localized to both cytoplasm and nucleus of ORS cells. Both interleukin (IL)-4 and IL-17 at 25 ng/mL upregulated the expression of PEDF of ORS cells, with IL-4 having the greater effect. PEDF 50 ng/mL decreased migration of ORS cells. CONCLUSIONS: PEDF is expressed in human cutaneous appendages and may play a modulatory role in the physiology of ORS cells.

Downregulation of 14-3-3ß and 14-3-3ζ in lesions of psoriasis vulgaris.

BACKGROUND: The 14-3-3 proteins are a family of conserved regulatory molecules expressed in all eukaryotic cells, which play essential roles in a wide range of vital regulatory processes, including differentiation, proliferation and transformation. In mammalian cells, seven 14-3-3 isoforms (ß, γ, ε, η, θ/τ, σ and ζ) have been identified, and each of these seems to have distinct tissue localizations and isoform-specific functions. 14-3-3ß and 14-3-3ζ are two important members of the 14-3-3 family. AIM: To explore the role of 14-3-3ß and 14-3-3ζ in normal skin and psoriasis vulgaris (PV) skin. METHODS: Using immunohistochemistry and western blotting, we measured expression of 14-3-3ß and 14-3-3ζ in 30 PV lesions and 15 normal skin samples. The average optical density (OD) of immunostaining and the relative grey scale of immunoblotting for 4-3-3ß and 14-3-3ζ were analysed by the t-test. RESULTS: The average OD of immunostaining for 14-3-3ß and 14-3-3ζ was 0.17 ± 0.00 and 0.24 ± 0.01, respectively, in psoriatic lesions, which was significantly lower than in normal controls (0.22 ± 0.01 and 0.37 ± 0.02, respectively; P < 0.01 for both). There was also a significant difference in the relative grey scale of 14-3-3ß and 14-3-3ζ (0.52 ± 0.03 and 1.44 ± 0.06, respectively) in psoriatic lesions compared with normal control tissue (3.32 ± 0.15 and 2.76 ± 0.11, respectively; P < 0.01 for both). CONCLUSIONS: Expression of 14-3-3ß and 14-3-3ζ were lower in psoriatic lesions than in normal human skin tissue. We speculate that 14-3-3ß and 14-3-3ζ may be involved in the regulation of normal skin function, thus decreased expression of 14-3-3ß and 14-3-3ζ might precipitate the disturbance in proliferation and differentiation of keratinocytes seen in psoriasis.

Mutagenesis of tGCN5 core region reveals two critical surface residues F90 and R140.

Tetrahymena General Control Non-Derepressor 5 (tGCN5) is a critical regulator of gene transcription via acetylation of histones. Since the acetylation ability has been attributed to the "core region", we perform mutagenesis of residues within the tGCN5 "core region" in order to identify those critical for function and stability. Residues that do not participate in catalysis are identified, mutated and characterized for activity, structure and thermodynamic stability. Variants I107V, Q114L, A121T and A130S maintain the acetylation function relative to wild-type tGCN5, while variants F90Y, F112R and R140H completely abolish function. Of the three non-functional variants, since F112 is mutated into a non-homologous charged residue, a loss in function is expected. However, the remaining two variants are mutated into homologous residues, suggesting that F90 and R140 are critical for the activity of tGCN5. While mutation to homologous residue maintains acetylation of histone H3 for the majority of the variants, the two surface-exposed residues, F90 and R140, appear to be essential for tGCN5 function, structure or stability.

Dyspepsia and irritable bowel syndrome in China: a population-based endoscopy study of prevalence and impact.

BACKGROUND: Dyspepsia and irritable bowel syndrome (IBS) are common in Western populations. AIM: To determine the epidemiology of dyspepsia and IBS in China. METHODS: A representative sample of 18 000 adults from five regions of China were asked to complete the modified Rome II questionnaire; 20% were asked to complete the 36-item Short Form Health Survey (SF-36). Participants from Shanghai were invited to provide blood samples and undergo oesophago-gastroduodenoscopy. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined using a multivariate logistic regression model. RESULTS: The survey was completed by 16 091 individuals (response rate: 89.4%). Overall, 387 participants (2.4%) had dyspepsia and 735 (4.6%) had IBS. All SF-36 dimension scores were at least five points lower in individuals with than without dyspepsia or IBS (P < or = 0.001). In Shanghai, 1030 (32.7%) of the 3153 respondents agreed to endoscopy; neither dyspepsia nor IBS was found to be associated with reflux oesophagitis, peptic ulcer disease or Helicobacter pylori infection. CONCLUSIONS: Prevalence estimates for dyspepsia and IBS in China are lower than in Western populations. In China, dyspepsia or IBS symptoms are generally not associated with underlying organic disease.

Overexpression of Csk-binding protein contributes to renal cell carcinogenesis.

C-terminal Src kinase (Csk)-binding protein (Cbp) is a transmembrane adaptor protein that localizes exclusively in lipid rafts, where it regulates Src family kinase (SFK) activities through recruitment of Csk. Although SFKs are well known for their involvement in cancer, the function of Cbp in carcinogenesis remains largely unknown. In this study, we reported overexpression of Cbp in more than 70% of renal cell carcinoma (RCC) specimens and in the majority of tested RCC cell lines. Depletion of Cbp in RCC cells by RNA interference led to remarkable inhibition of cell proliferation, migration, anchorage-independent growth as well as tumorigenicity in nude mice. Strikingly, silencing of Cbp negatively affected the sustaining of Erk1/2 activation but not c-Src activation induced by serum. Besides, the RhoA activity in RCC cells was remarkably impaired when Cbp was knocked down. Overexpression of wild-type Cbp, but not its mutant Cbp/DeltaCP lacking C-terminal PDZ-binding motif, significantly enhanced RhoA activation and cell migration of RCC cells. These results provided new insights into the function of Cbp in modulating RhoA activation, by which Cbp might contribute to renal cell carcinogenesis.

Expression and localization of vascular endothelial growth factor and vascular endothelial growth factor receptor-2 in human epidermal appendages: a comparison study by immunofluorescence.

BACKGROUND: Vascular endothelial growth factor (VEGF) promotes angiogenesis and plays important roles in neovascularization and development of tissues. VEGF receptors (VEGFRs) are high-affinity receptors for VEGF and are originally considered specific to endothelial cells. We have previously shown that keratinocytes from human normal skin express VEGFRs. This poses the question of whether these receptors are also expressed by epidermal appendages, as epidermal appendages are lined with epithelial cells. OBJECTIVE: To investigate the expression of VEGFR-2 compare with VEGF in epidermal appendages, including hair follicles, eccrine sweat glands and sebaceous glands. METHODS: Monoclonal antibodies to VEGF and VEGFR-2 were used for immunohistochemical examination of cryostat-cut sections of normal human skin specimens from 11 donors undergoing cosmetic surgery. RESULTS: Immunoreactivities for VEGF and VEGFR-2 principally showed parallel intense expression in anagen hair follicle (including outer root sheat, inner root sheath, dermal papillae epidermal matrix), sebaceous glands (ductal and secretory portions) and eccrine sweat glands (ductal and secretory portions), respectively. In particular, abundant expression of VEGF was found in the follicular basement membrane zone surrounding the bulb matrix and in the ductal and secretory portions of eccrine sweat glands. CONCLUSION: A potential VEGF/VEGFR-2 autocrine pathway may be defined by the coexpression of VEGF and VEGFR-2 in human skin epidermal appendages.

Polymerase chain reaction based C4AQ0 and C4BQ0 genotyping: association with systemic lupus erythematosus in southwest Han Chinese.

OBJECTIVE: To investigate the association of complement C4 null genes (C4Q0, including C4AQ0 and C4BQ0) and C2 gene with systemic lupus erythematosus (SLE) in southwest Han Chinese; 136 patients with SLE and 174 matched controls were genotyped. METHODS: C4 null genes were determined by a polymerase chain reaction (PCR) procedure with sequence specific primers (PCR-SSP). The 2 bp insertion in exon 29, which was previously identified in non-Chinese populations and caused defective C4A genes, was directly typed by sequencing the whole exon 29 using exon specific primers. The exon 6 of complement C2 was also sequenced in both the patients and controls. RESULTS: The frequency of homozygous C4AQ0 allele was 12.5% (17/136) in patients with SLE compared with 1.1% (2/174) in controls (p<0.001, odds ratio (OR)=12.286, 95% confidence interval (95% CI) 2.786 to 54.170). There was no significant difference for homozygous C4BQ0 allele between patients with SLE and controls (p=0.699). Patients with the C4AQ0 gene had an increased risk of acquiring renal disorder, serositis, and anti-dsDNA antibodies compared with those without C4AQ0 (for renal disorder, p=0.018, OR=8.951, 95% CI 1.132 to 70.804; for serositis, p=0.011, OR 4.891, 95% CI 1.574 to 15.198; for anti-dsDNA, p=0.004, OR 7.630, 95%CI 1.636 to 35.584). None of the patients or controls had the 2 bp insertion in exon 29 of the C4 gene. The type I C2 deficiency was not detected in the 310 samples. CONCLUSION: It is suggested that deficiency of C4A (not due to a 2 bp insertion in exon 29), but not C4B or C2, may be a risk factor for acquiring SLE in south west Han Chinese; this results in increased risk of renal disorder, serositis, and anti-dsDNA antibodies in patients with SLE. Racial differences seem to be relevant in susceptibility to SLE

[Research on fibrotic effect of Ni-Ti and 317L alloys in esophagus].

This study was conducted to examiune the fibrotic effect of Ni-Ti and 317L alloys in esophagus. The extract fluid from Ni-Ti, 317L alloys was made according to the ASTM standards of U.S.A. The Fb of esophageal scar was cultured primarily, then incubated with alloy abstract fluid. The proliferating activity of Fb was measured by MTT at 4, 24, 48, 72 hours in the course of culturing. The esophagus embedding test of Ni-Ti, 317L alloys was made according to ASTM standards of U.S.A. The tissue around the alloys was taken at weeks 2 and 12, and the pathologic changes were analysed. The results showed that Ni-Ti, 317L extract could depress the proliferating function of Fb gently, and the depressing action increased gradually with the culturing time. The result of embedding test was in accord with the ASTM standards of U.S.A. completely; the fibrotic membrane around the NiTi, 317L alloys became thinner with embedding time. These findings suggested that the scattering composition of Ni-Ti, 317L in body fluid might not activate the proliferating and secreting function of Fb, and the two alloys could not lead to fibrosis of esophagus aroun them.